February 25 - March 2, 2024: Issue 615


Ancient Fish Habitat Despoiled: Curl Curl Creek Choked With Silt - Runs Into Manly Creek - Manly Dam

On January 24, 2024 the Save Manly Dam Bushland group brought attention to silt runoff in Curl Curl Creek.

Posting on Facebook the SMDCC  stated;

'In 2020, the Sydney Morning Herald published an article outlining fears for the future of the Climbing Galaxias fish at Manly Warringah War Memorial Park - due to impending developments in the upper catchment.

This ancient relic's very last habitat in Greater Sydney was "Curl Curl Creek"- (the main feeder creek to Manly Dam's reservoir). It can only survive in clean fresh water. 

After significant vegetation clearing at the new Forest High School site on Allambie Rd,  several people have now reported extensive amounts of mud in the creek. For years the community has been asking for special measures to protect one of the few "A grade" creeks on the Northern Beaches and for a management and recovery plan to be put in place for the Gondwanan Fish (to no avail).  

Sadly we now have photos (below) which reveal that the, once pristine, waterway is now smothered in mud and silt.  This could sadly mean that the Climbing Galaxias, which have existed in this area for 90 million years, are now locally extinct. 

(Photo 4 portrays the NSW Dept of Education construction site at Manly Vale in 2018 - when huge volumes of sediment were also released into the waterway).

Northern Beaches Council and the Environmental Protection Authority have been contacted but we have received no feedback yet.

Meanwhile, Council is commencing to clear yet more bushland at the dam for a plastic fibre boardwalk.'

The Climbing Galaxias, Galaxias brevipinnisfish's common name comes from the Climbing Galaxias' ability to climb damp rock faces and waterfalls tens of metres high. The fish achieves this by facing up the incline, spreading the large pectoral and pelvic fins against the substrate, and wriggling the body with lizard-like movements.

During 1999 the Climbing Galaxias was the focus of a major conflict between conservationists and developers in one area of northern Sydney. The fish in the image are from Curl Curl Creek, a feeder creek which drains into Manly Dam, situated in the Manly Warringah Memorial Park in Manly Vale, Warringah Shire. These fish are part of the only confirmed landlocked population of Climbing Galaxias occurring in the Sydney area, and one of the most northern Australian populations recorded in the databases of the Australian Museum.

Habitat: It prefers clear, tumbling waters in the headwaters of streams flowing through forested land. The fish breathes through its skin and uses large pectoral and pelvic fins as suction cups to scale even waterfalls. In other places the fish’s larvae rely on reaching the sea to start feeding.

A Climbing Galaxias photographed at night in Manly Dam, Sydney, New South Wales, December 2008. Image: © Jodi Rowley

On February 2nd, 2024, for World Wetlands Day, SMDCC posted more photos, stating:

"Curl Curl Creek" feeds into Manly Dam at Allambie Heights (then becomes "Manly Creek" on the other side of the reservoir).

It was classified in the very top category of all Northern Beaches Creeks for its excellent water quality and high levels of biodiversity (see report dated 2014-2015).

Last week a torrent of silt was allowed to flow from the new Forest High School building site, on Allambie Rd, into this fragile waterway (see photos). 

Wetlands absorb 40 times more carbon than rainforests. They cover just 7% of the planet but are home to 40% of the world's biodiversity.'' the group stated

On February 11, 2024 the Guardian ran a report 'Sydney’s 90m-year-old climbing galaxias fish may have been wiped out by school building works' by Peter Hannam.

That report states:
'Northern Beaches council has also warned more silt run-off was possible. It told the SMDCC treasurer, Ann Collins, on 25 January – more than a week after the first event – a nearby sediment basin “appeared to be at capacity and would not be able to cope with another large rain event”, according to correspondence seen by Guardian Australia.'

'The New South Wales Environment Protection Authority said it had sent staff on 19 and 22 January who confirmed siltation of the creek and its source, the Forest high school. Initial investigations singled out the school works, although additional sources of silt may be found.

“We advised the contractor and the NSW Department of Education to take immediate action to prevent water pollution,” a spokesperson said. “The colouration of the water may be around for some time until it naturally flushes, as the silt is from fine clay.”

The EPA “has not been monitoring the climbing galaxias population”, the spokesperson said, with the council the appropriate body to conduct any monitoring. However, “at this stage, it appears no aquatic life has been impacted by the incident”.

For its part, the education department said its works weren’t to blame for the siltation even though it was the only party asked by the EPA to take action.'